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(No Model.) I

J. D. EHRMANN. FRIUTION CLUTCH.

No. 427,257. Patented May 6, 1890.

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UNITED STATES Artur FFICEQ JOHN D. EHRMANN, OF KAUKAUNA, IVISCONSIN, ASSIGNOR TO THE ATLAS IRON AND BRASS IVORKS, OF SAME PLACE.

FRICTION-CLUTCH.

SPECIFICATION forming part of Letters Patent No. 427,257, dated May 6, 1890.

I Application filed August 3, 1889. Serial No. 319,614. (No model.)

To all whom. it may concern:

Be it known that 1, JOHN D. EHRMANN, of Kaukauna, in the countyof Outagamie and State of Visconsin, have invented new and useful Improvements in Friction-Clutches; and I do hereby declare the following to be a full, clear, and exact description of said invention, reference being had to the accompanying drawings, and to the letters of reference to marked thereon, which form a part of this specification.

My invention relates to a clutch which is adapted for use with an elevator.

In the drawings, Figure l is a side elevation of the complete device. Fig. 2 is a central longitudinal section of the same device. Fig.

part of the arm of a segment-bearing. Fig. t is a detail of a housing. Fig. 5 is a detail 2o of a connecting-link and the parts to which it is attached.

The same letters refer to like parts in all the views.

A is a shaft, on which is the loosepulley B, 2 5 the pulley being provided with a rim 0, projecting laterally from the supporting-spokes D D. A spider E is provided with a rigid hub F, which hub is supported rigidly on the shaft A, being secured thereon by a spline G. The spider shown in the drawings has four arms, which number is deemed preferable, though any other number may be used. Segment-bearin gs H H, having outward faces adapted to bear against the inner face of the 5 rim 0 of the pulley, are each provided with an inwardly-extending arm I, which arms are fitted and adapted to slide endwise in grooves therefor in the outer faces of the arms of the spider E, the arms I I being held movably in 40 theirways in the arms of the spider by the bars K K, affixed rigidly to the arms of the spider in front of the grooves in which the arms I I slide. The segments II II are thrown into and out of engagement with the rim of 5 the pulley by means of the bent levers L L, the inner end of each of which entersa recess M therefor in the arm I. The levers L L are fulcrumed on links N N, to the outer ends of which the levers are pivoted, the inner ends of the links being pivoted on a ring 0, which ring is supported inovably on the hub F of the spider, and may be adjusted out or in on o is a detail of one arm of the spider and a the hub by means of the ring P, which turns in a screw-thread on the hub F, and to which the ring 0 issecured movably by means of the set-screws R R, turning through lugs S S, rigid on ring 0, into a peripheral groove therefor in the ring P. The sides of the heads L L of the levers L L are curved and bear movably against the outer and inner walls of the recesses M M. The links N N are preferably arranged at an angle to the line of motion of the armsI I, as shown in Fig. 2.

The outer extremities of the levers L L are bent inwardly toward the shaft A and at their ends are pivoted to the inner ends of the links T T, which links at their outer ends are pivoted in a shifting hub U, which hub has endwise movement on the shaft A, but is held to a rotary movement therewith by the spline G, and yoke V rides in a groove therefor in the hub U, which yoke is adapted to receive a lever for shifting the hub U forward and back on the shaft A.

It will be understood that the segments II H are in engagement with the inner surface of the rim 0 of the pulley B when the bent levers L L and hub U are in the position shown in Fig. 2, and that at the same time the levers L L are locked in that position by reason of the links T T being at right angles to the axis of the shaft A. It will also be understood that by sliding the hub U outwardly along the shaft A from the position shown in Fig. 2 the outer ends of the levers L Lwill be released from the locking force of the links T '1 against them, and by the further outward movement of the hub U the outer ends of the levers L L will be carried outwardly, whereby by the tilting of the levers L L the segments H II will be thrown out of engagement with the rim O of the pulley B. The outer arms of the levers L L being longer than the inner arms, the centrifugal force existing when they rotate with the shaft forces them away from 9 5 the shaft when not held thereto by the links T T, thereby drawing the inner ends of the levers toward the shaft, carrying the segments away from the rim of the pulley and obviatin g the liability of engagement of the seg- I03 ments with the rim of the pulley by the more force of centrifugal motion.

' For holding the inner ends of the levers L L up to their work, the bars K K are provided with housing IV, adapted to receive and retain therein the outwardly-projecting ends of the pin Y, passing through the link N and lever L, which pin is preferably provided on its outer ends with small sleeves or frictionwheels Y Y.

For the purpose of providing as much surface as possible for the bearing of the segm ents H H against the rim of the pulley with out making them too wide for convenience in casting, the outer surface of the segments and the inner surface of the rim of the pulley are preferably grooved or serrated in the manner shown in Fig. 2, and for facing the segments against the surface of the rim of the pulley as perfectly as possible Babbitt or other soft metal H is affixed to the outer surface of the segments II H by casting it thereon, it being secured to the segments by means of roughness of the surface or slight apertures therefor. By means of this metal shoe H a much more perfect bearing and considerable friction against the rim of the pulleyare obtained than could otherwise be had, and thereby the value of the clutch is greatly enhanced.

I do not claim, broadly, the combination of radially-movable friction-arms, their operating-levers, and simultaneously adjustable fulcra for the operating-levers, as such subject-matter is not new with me.

'What I claim as new, and desire to secure by Letters Patent, is

1. In a clutch, the combination, with a spider and a radially-movable arm thereon, of a lever L and a link N, on which the lever L is fulcrumed, which link is pivoted to a ring on the hub of the spider, substantially as described.

2. In a clutch, a swinging link N and a lever L, fulcrumed on the swinging link N, in combination with a shifting hub U, having movement endwise on a shaft A, and a link T, pivoted at its outer end on the hub U and at its inner end pivoted to the end of the lever L, the link T being so constructed and located that the end of the link pivoted to the hub U is always at a greater distance from the shaft than the other end of the link is, and so that as the hub U is moved toward the lever L, forcing the lever up to its work, the link T comes to a position nearly at right angles to the axis of the shaft, substantially as described.

3. In a clutch, a spider aifixed to and 1'0 tating with a shaft and an arm I, adapted to move radially in the arm of the spider, in combination with a lever L, a swinging arm N, on which the lever L is pivoted, a housing W, affixed to the arm of the spider, and a pin Y, having projecting ends adapted to enter and be retained in the housing WV, whereby the lever L is held up to its work, substantially as described.

4. In a clutch, a radially-reciprocating arm I and a lever L, pivoted on a swinging arm N, in combination with a housing WV, affixed to the arm of a spider, in which arm the radially-moving arm I travels, and pin Y, having projecting ends adapted to be received and retained in the housing WV, whereby the lever L is held up to its work, substantially as described.

5. In a clutch, the combination, with a spider and an arm movable radially thereon, of a lever at one end engaging the radiallymovable arm and a link on one end of which the lever is fulcrumed, which link at its other end is pivoted to a ring onthe hub of the spider, the link being so constructed and located that the end that is pivoted to the lever is always nearer to the axis of the line of motion of the radially-moving arm than the other end is, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

JOHN DH'EI-IRMANN. Witnesses:

G. II. DAWSON, LEONARD B. SAGE. 

